Naukri Interview Questions, Process, and Tips

Threads are lightweight units of execution within a process, while processes are independent instances of a program.

• Threads share the same memory space and resources of a process, while processes have their own memory space and resources.

• Threads are faster to create and terminate compared to processes.

• Threads within a process can communicate with each other directly, while processes communicate through inter-process co...read more

Threading at the CPU level involves the execution of multiple threads simultaneously to improve performance.

• Threading allows for parallel execution of tasks on a CPU.

• Threads are scheduled by the operating system and executed by the CPU.

• Each thread has its own stack and program counter.

• Threads share the same memory space, allowing for communication and data sharing.

• Thread synchronization mechanisms like locks and semaph...read more

Thrashing is a phenomenon in computer systems where excessive paging occurs, leading to a decrease in overall system performance.

• Thrashing occurs when a computer's virtual memory system is constantly swapping data between RAM and disk.

• It typically happens when the system is overloaded with too many processes or when the working set of a process exceeds the available physical memory.

• Thrashing can severely impact system ...read more

Page replacement policies are algorithms used in operating systems to decide which pages to evict from memory when a new page needs to be loaded.

• FIFO (First-In, First-Out): Evicts the oldest page in memory.

• LRU (Least Recently Used): Evicts the least recently used page in memory.

• LFU (Least Frequently Used): Evicts the least frequently used page in memory.

• Optimal: Evicts the page that will not be used for the longest per...read more

Queue is a data structure that uses FIFO (First-In-First-Out) principle.

• Elements are added to the back of the queue and removed from the front.

• Common operations include enqueue (add element) and dequeue (remove element).

• Examples: waiting in line, printing tasks in order.

Paging is a memory management technique used by operating systems to efficiently manage memory.

• Paging divides the physical memory into fixed-size blocks called pages.

• Virtual memory is divided into fixed-size blocks called page frames.

• When a process needs to access a memory location, the operating system maps the virtual address to a physical address.

• Page tables are used to keep track of the mapping between virtual and ...read more

Page faults occur when a program requests data from the disk that is not currently in the main memory.

• Page faults happen when a program tries to access data that is not present in the main memory.

• When a page fault occurs, the operating system needs to retrieve the required data from the disk and load it into memory.

• Page faults can significantly slow down program execution as disk access is much slower compared to memor...read more

ATM stands for Automated Teller Machine. It is an electronic banking device that allows customers to perform financial transactions.

• ATM is a self-service machine used for banking purposes.

• It provides services like cash withdrawal, balance inquiry, fund transfers, and bill payments.

• ATMs are available 24/7 and are located in various places like banks, shopping malls, and convenience stores.

• Customers can access their acco...read more

Yes, I have made a thread-based program in C.

• Threads in C allow for concurrent execution of multiple tasks.

• Threads can be created using the pthread library in C.

• Thread-based programs can improve performance and responsiveness.

• Example: Creating multiple threads to perform parallel processing tasks.

The 1PB file can be read using 4 threads by dividing the file into smaller chunks and assigning each thread to read a chunk.

• Divide the file into smaller chunks of equal size.

• Assign each thread to read a specific chunk of the file.

• Ensure synchronization between the threads to avoid conflicts.

• Combine the data read by each thread to obtain the complete file content.

The output will be 'Hello'.

• The code assigns the value 3 to the variable $a using the assignment operator (=).

• The if statement checks if the value of $a is truthy (non-zero, non-null).

• Since 3 is truthy, the condition evaluates to true and 'Hello' is echoed.

Ajax is a web development technique that allows for asynchronous communication between the client and server.

• Ajax stands for Asynchronous JavaScript and XML.

• It enables web pages to update content without reloading the entire page.

• Ajax uses XMLHttpRequest or fetch API to send and receive data asynchronously.

• Commonly used in dynamic web applications to enhance user experience.

• Example: Autocomplete search suggestions, rea

AJAX is a technique used to send and receive data from a server without refreshing the entire web page.

• AJAX stands for Asynchronous JavaScript and XML.

• It allows for asynchronous communication between the client and server.

• AJAX uses XMLHttpRequest object to send and receive data.

• Headers in AJAX requests contain additional information about the request or response.

• Common headers include Content-Type, Accept, and Authoriz...read more

An IP address is a unique numerical label assigned to each device connected to a computer network. It consists of 32 bits.

• IP address is used to identify and locate devices on a network.

• It is composed of four sets of numbers separated by periods.

• Each set can range from 0 to 255, representing 8 bits.

• Example: 192.168.0.1

Relational databases are structured databases that store data in tables with relationships. They are used for data integrity and flexibility.

• Relational databases store data in tables with rows and columns.

• They use structured query language (SQL) to manipulate and retrieve data.

• Tables can have relationships with each other through keys.

• Relational databases ensure data integrity and consistency through constraints.

• They p...read more

Left Inner Join is a type of join operation in relational databases that returns only the matching records from both tables.

• Left Inner Join combines rows from two tables based on a related column between them.

• It returns only the matching records from both tables.

• In C code, you can implement Left Inner Join using arrays by iterating through both arrays and comparing the related column values.

• Here's an example of C code

A primary key is a unique identifier for a record in a table, while a unique key ensures that all values in a column are distinct.

• Primary key is used to uniquely identify a record in a table.

• A table can have only one primary key.

• Primary key cannot have null values.

• Unique key ensures that all values in a column are distinct.

• A table can have multiple unique keys.

• Unique key can have null values.

UDP has advantages over TCP in terms of speed, simplicity, and low overhead.

• UDP is faster than TCP because it does not require the establishment of a connection before data transfer.

• UDP is simpler than TCP as it does not have features like flow control, congestion control, and error recovery.

• UDP has lower overhead compared to TCP as it does not include sequence numbers, acknowledgments, or retransmission mechanisms.

• UDP...read more

HTTP is a protocol used for communication between web browsers and servers.

• HTTP stands for Hypertext Transfer Protocol.

• It is the foundation of data communication for the World Wide Web.

• HTTP uses a client-server model where the browser acts as the client and requests data from the server.

• It operates on top of TCP/IP and uses port 80 by default.

• HTTP is stateless, meaning each request is independent and unrelated to previ...read more

HTTP request transfers data from client to server using headers.

• HTTP request is sent from the client to the server using the HTTP protocol.

• The request consists of a request line, headers, and an optional message body.

• Headers provide additional information about the request, such as the content type, cookies, authentication, etc.

• Some common headers include 'Content-Type', 'User-Agent', 'Authorization', 'Cookie', etc.

• Hea...read more

Reverse a linked list by changing the direction of the pointers.

• Iteratively swap the next and previous pointers of each node.

• Use three pointers to keep track of the current, previous, and next nodes.

• Repeat until the current node becomes null.

• Example: 1 -> 2 -> 3 -> 4 -> null becomes 4 -> 3 -> 2 -> 1 -> null.

MVC framework is a software design pattern that separates an application into three interconnected components: Model, View, and Controller.

• Model represents the data and business logic of the application.

• View is responsible for displaying the user interface.

• Controller handles user input, updates the model, and interacts with the view.

• The workflow starts with the user interacting with the view, which triggers a request t...read more

JSON is a lightweight data interchange format. XML is a markup language used for structuring and storing data.

• JSON stands for JavaScript Object Notation.

• JSON is easy to read and write for humans and easy to parse and generate for machines.

• JSON uses key-value pairs to represent data.

• XML stands for eXtensible Markup Language.

• XML uses tags to define elements and attributes to provide additional information about elements.

• ...read more

JSON is better than XML for data interchange due to its simplicity, readability, and smaller file size.

• JSON is more lightweight and has a simpler syntax compared to XML.

• JSON is easier to read and write for humans.

• JSON has better support for arrays and objects.

• JSON has a smaller file size compared to XML.

• JSON is faster to parse and process compared to XML.